Because you're writing Java, which is a very verbose language, all code completion and code generation (method stubs, auto constructors etc.) are a godsend when working with Android.
That's why I'm always wondering why anyone would so much want to waste time with typing Java on VIM (even though I DO use Vim for other programming tasks) instead of just using an IDE specifically customized to make such development faster and easier.
A few years ago I was having lunch with some of the guys from Franz Lisp and one of them said that his epiphany was that Java did have macros, but that they were write only and built into the IDE. I didn't really appreciate his insight at the time but I get it now.
That's why I'm always wondering why anyone would so much want to waste time with typing Java on VIM (even though I DO use Vim for other programming tasks) instead of just using an IDE specifically customized to make such development faster and easier.